Gippsland Blackwood Plantation Management Workshop

On Sunday afternoon 22nd April the Gippsland Agroforestry Network (GAN) held a blackwood workshop. The aim was to look at the options of managing a blackwood plantation and put some theory into practice.

In 2011 about a hectare of blackwood was planted on an alluvial creek flat as part of a stream front revegetation project. The blackwoods were planted as tubes at a spacing of 2m x 2m. The intention was to encourage straight vertical growth of the young trees and to restrict their propensity to fork and branch. The trees are now in the order of 6m tall and ranging from 8 to 15 cm diameter at breast height (1.3m).

The field day discussed the New Zealand view that the only way to control the blackwoods enthusiasm to fork and branch was to continually (annually) form prune and to remove any side branches from the central stem if they were more than 2cm in diameter. Viewing the trees, it was considered that this was probably the best option as despite being form pruned in 2014 (as 3yo stems) and lift pruned to 2m in 2015, there was considerable forking and co-dominant stems that had emerged since. The conclusion was that form pruning should have been carried out as an annual activity (at least) over the past 3 years.

I hope the field day discussed the New Zealand 3 principles of good blackwood management.

So what is the first of the three principles?

Good site selection.

Was there any discussion about the planting site in terms of rainfall, soils and wind exposure? Without good site selection the chances of success are very limited.

What is the second principle?

2. Good establishment.

The trees were tube stock planted at 2×2 m spacing.

What was the site preparation?

What was the weed control?

Was any fertiliser added?

Was any browsing protection/control used?

And finally what is the third principle?

3. Good management.

We know the trees were form pruned in 2014 and lift pruned in 2015.

New Zealanders talk about annual browsing control, weed control and pruning.

Was weed control used in the first few years?

Every blackwood field day/workshop should focus on the New Zealand 3 Principles.

The need to thin the plantation was also discussed. Clearly, the trees were competing given the close planting and a number had died. Small lower branches above the 2m lift prune were largely dead, significant leaf fall had occurred and the ground beneath the trees was totally bare. Misshapen trees were identified for culling and there was debate as to the best way to remove them. Stem injection was considered but rejected due to the risk of flashback. It was decided that cutting at ground level was the best option with the wallaby population taking care of the regrowth. There was also discussion as to the extent of the thinning. Removing all the identified trees (about 60%) would remove much of the vertical stimulus and probably encourage further forking . As a result, it was agreed that about half the identified trees would be removed this winter and the rest in 12 months. It was noted that this would also reduce the amount of debri on the ground at the one time. The proposed thinning would reduce the density from the current 2000 stems / ha to about 1400 with the second half of the thinning reducing this to about 800.

Lift pruning was then carried out on the selected trees to about 4m and further form pruning was undertaken.

It would be interesting to see what his plantation looks like after some thinning and pruning.

Judging by the photos there would appear to be an opportunity to rescue this plantation.

8 responses to “Gippsland Blackwood Plantation Management Workshop”

Sorry to be blunt but yet another example of how not to do things. It’s frustrating to think that silvicultural info on how to correctly establish and manage blackwood plantations has been around since 2002 (NZ) and 2004 (PFT , Tasmania).

It’s been on the internet all that time, rather available I would think. Only problem with people coming up with their own ideas is I haven’t seen too many of them work, only poor outcomes that does nothing to encourage growers.

So can either of you come up with something constructive about what you think a management workshop such as this one should recommend for this site? I don’t think it is helpful to make comments about the site needing “rescue” and suggesting that NZ and PFT nailed blackwood management over ten years ago without any definitive references to case studies backing up those claims.

If you read the blogs and other material on the NZFFA WWW site it’s clear that the NZ growers are still refining their approach. And I asked Stu on this site some time ago for case studies of successful blackwood plantations in Tasmania which would presumably demonstrate the management regime required. All he could come up with was one writeup of a visit to a plantation where the management regime had changed substantially over time and there still hadn’t been a substantial commercial harvest. Not an indicator that blackwood management in Tasmania is all sorted IMO.

And to say the site that’s the subject of this post needs rescue implies it is in a dire state which is not the case. The point of the workshop was to identify the management regime going forwards based on experience to date.

I had a very pleasant time visiting some excellent farm grown trees last weekend at a bunch of sites between Bendigo and Ballarat. Very enjoyable discussions with people who are getting on with growing good quality trees but who are interested in constructive comments … and how they can make a quid from the trees. Perhaps those themes should be the focus from people who would like to see the sector grow. (Gordon is doing a great job on the markets side of things.)

Obviously the internet is not “available” enough for some. It reminds me of the adage “only read the manual after exhausting all other possibilities of success”. That’s just the way some people are.

Actually the fact that people keep planting blackwood when Governments, the forest industry, farming associations, and the market refuse to offer any support I find extraordinary. Is it defiance?

Yes DIY blackwood is a 90% road to failure. Some by luck or chance do succeed. Gilles Carrabin is a rare example of DIY success (with a little encouragement from yours truly).

Which leads me to the GAN workshop!

Yes the plantation in question is a classic case of DIY blackwood.

So if a workshop comes along and attempts to “learn” from the DIY, it can only do so within the context of the existing guidelines. Otherwise the workshop risks perpetuating the DIY attitude to plantation blackwood. Hence Stuarts comment of frustration. And my response about the Three Principles…

Neither Stu or I wish to see the perpetuation of DIY blackwood (see below for exceptions). Please!!!

There is still much for us to learn about plantation blackwood so a bit of DIY is to be encouraged. But it must be DIY within the context of knowledge and understanding. Learn to grow blackwood properly according to the rules first, and then DIY!

The fact that this Gippsland DIY blackwood CAN be rescued is not a criticism but a positive. Most DIY blackwoods never get rescued.

If people are offended by my language then I apologise. That is not my intent. Anyone who wants to grow blackwood has my complete support. But DO read the manual first. And talk to someone who has some experience and understanding.

David, the NZ bwd regime as recommended by the late Ian Nicholas has pretty much got it right. It’s based on extensive field trials and reseach with results on the ground. If no one is going to make constructive critcism of plantings such as the one outlined above then others are more likely to make the same mistakes in the future. At a spacing of 2x2m they have planted 2500 sph. Seedlings and planting come at a cost. Then there is the huge job and cost of thinning to 150-200 sph final stocking. Having done a fair bit of economic modelling of plantations in the past I can assure you there has been a loss of 2-3 percent on internal rate of return by planting and thinning such large numbers. Even if the cheaper thinning option is undetaken and trees are felled and left on site the fire risk is considerable and the entire stand is at risk. Yes the stand does need rescuing for several reasons.
Bwd silviculture as per NZ and PFT recomendations should not be altered to any great extent. The initial stocking is about right (800 sph for a selection ratio of about 4:1), regular form pruning and thinning to 150-200 sph final crop by about about age 10. This is backed up by results on the ground.
Where I personally take it further is the use of a nurse crop, as some growers in NZ also do, against the recommendation of Ian Nicholas. I have proven it works very effectively on a site near Sheffield in northern Tas. Ian Nicholas inspected this site a year or so before his passing and he congratulated me on the form achieved in the blackwood. It is an exposed site and the best you do without a nurse crop would be 3-4m of relatively straight butt log while I’ve achieved 6-7m and near dead straight with a selection ratio of less than 4:1. The shame about this site is the landowners and pft failed to complete thinning but it demonstrates what a nurse crop can do for exposed sites. Gordon has seen this site but unfortunately just passes it off as not a suitable site for blackwood and failed to grasp the potential for utilisation of a nurse crop on sites that are exposed to wind – bwd can handle wind and grow well, its just form that is badly affected by wind.

a/ I don’t know why the initial planting was at 2500sph. I agree that this is high based on lessons learnt in NZ. FWIW I’m generally planting at 400-600sph at our block based on genetics and species.

b/ Discussion about sph, silviculture, nurse crops etc is all very well but is not much use without ground truthed data – ideally from local plots – to substantiate the stance. And as I mentioned previously, various NZFFA blackwood specialists are refining their model based on recent information through the NZFFA WWW site.

I encourage both of you to post measurement data from local plots with details of planting sph, genetics and silviculture. Particularly any plots that have made it through to harvest with details of grade, volume and sale price. Without this local data to back up statements on sph and silviculture can anyone local claim the experience and understanding Gordon mentions?

FWIW I think this is an issue across Australian farm forestry in general. Anyone reading this who is contemplating farm forestry for profit and considering engaging some assistance on what to plant and how to manage the trees all the way to harvest, might ask the putative source of assistance how many trees they have taken through from planting to harvest and how much profit did the farmer make after subtraction of harvest and transport costs? Let alone other planting and silvicultural costs and any opportunity cost from foregoing or reducing other returns from the land.

IMO by careful design, incorporation into a farm and management there is opportunity for attractive profit but it’s not straightforward.